Elderly U.S. development worker Warren Weinstein has appeared in an al-Qaeda video for the first time since he was kidnapped in Pakistan just days before he meant to return home last August.

The American aid worker pleaded with U.S. President Barack Obama to meet his captors’ demands for the release of prisoners in order to save his life, in a video released by the militant group’s media arm.

“My life is in your hands, Mr. President. If you accept the demands, I live; if you don’t accept the demands, then I die,” it quoted Weinstein as saying in the video, which was posted on Islamist websites on Sunday.

He also tells his wife Elaine that “I’m fine, I’m well, I’m getting all my medications, I’m being taken care of.”

The two minute, 40 second video was posted on jihadist forums by al-Qaeda’s media arm as-Sahab on Sunday, according to the U.S. monitoring service SITE. There is no sign of when the video was made and Weinstein appears alone before the camera.

Al-Qaeda leader Ayman al-Zawahiri said in an audio recording in December that the group was responsible for Weinstein’s abduction and demanded the release of all those in U.S. detention for ties his Islamist militant group or the Taliban.

Zawahiri demanded that Washington end air strikes in Afghanistan, Pakistan, Somalia and Yemen, and release the 1993 World Trade Centre bombers along with relatives of Osama bin Laden.

There was no response from the U.S. embassy in Islamabad. Pakistani security officials said they were not immediately aware of the video but believe Weinstein is being held by al-Qaeda and local Taliban near the Afghan border.

Pakistan last month deported bin Laden’s widows and children to Saudi Arabia, a year after they were detained following the U.S. commando operation that found and killed the al-Qaeda founder in Abbottabad.

Secretary of State Hillary Clinton said Monday that the U.S. believes Zawahiri is in Pakistan, vowing to keep up pressure on Islamabad to crack down on Islamist militants during a visit to the country’s arch-rival India.

Weinstein was snatched after gunmen tricked their way into his Lahore home on August 13, shortly before he was due to return home after seven years in Pakistan.

He was country director for U.S.-based consultancy J.E. Austin Associates, which does contracting work with the U.S. government’s development agency, USAID.

Security officials believe Weinstein is being held in Pakistan’s lawless northwestern tribal belt, probably close to North Waziristan, which is the focus of U.S. drone strikes targeting al-Qaeda and the Taliban.

Informants have suggested he is moved regularly to avoid detection.

“He is with al-Qaeda and local Taliban, but we are unaware about his exact location,” one Pakistani official told AFP on condition of anonymity.

A Pakistani working for J.E Austin told AFP that the company had not received any demands for Weinstein’s release, nor for a ransom.

“We came to know that Weinstein is with al-Qaeda through the media. You see their demands are of state level and we are not in a position to fulfil these,” he told AFP on condition of anonymity.

Weinstein’s kidnapping started a wave of abductions of foreign aid workers.

On April 29, British aid worker Khalil Dale was found beheaded in the southwestern city of Quetta, with a note from his captors saying he had been killed because their demands were not met.

He was snatched on January 5. A German aid worker and his Italian colleague remain in captivity. A Kenyan aid worker kidnapped in January was released around three months later, a Kenyan diplomat told AFP, giving no further details.

A Swiss couple snatched in July last year were held for nine months before claiming to have escaped in March, but the nature of their liberation is clouded in mystery.